Method for the separation of chemically modified rosins and their esters into components



Patented Feb. 20,1940

. UNITED STATES] METHOD Fon THE SEPARATION, OF, CHEMI- CALLY MODIFIED ROSINS AND THEIR- ESTERS INITQQOMPONENTS I Joseph N. Borglin, Wilmington, Del., assignor to Hercules Powder Company, Wilmington,

Del.,

a corporationof Delaware No Drawing.

Application September 28,1939, Serial No. 296,944

10 Claims (or mo -103) This invention relates toa method for the separation of chemically modified rosins and their esters into components; and more particularly the separation of chemically modified resins and their esters into components by treatment with a selective solvent. 7 1

Due to the complexity of the chemical structure of rosin, treatments for the production of chemical modifications practically always result 10 in products which are mixtures of two or more chemical compounds. The product may contain unchanged rosin or the rosin may be converted into two or more .difierent materials, or both. The esterification of such a modified product produces a modified rosin ester which, similarly,

Like- 5 is a mixture of. chemically different esters. wise, esterification of rosin and then treatment to produce chemical modification, gives a product ters.

Thus, for example, the' hydrogenation of "rosin may result in a mixture of unchanged rosin and dihydro-rosin. More complete hydrogenation results in a mixture of dihydro-rosin and tetrahydro-rosin. Theproduction of a product'whioh is entirely tetrahydro-r'osin has so far proved impossible. The est-erification of a hydrogenated rosin results in a mixture of resin esters. Likewise, the hydrogenation of rosin esters results in a mixture of. ordinary rosin, ester and dihydrotetrahydro-rosin ester; a

The separation of the chemically different components of the chemically modified rosins'has' 5 heretofore been practically impossible, and the mixtures of compoundsv of difierent chemical structure. No successful method for separating the components of'such mixtures has been devalue from a commercial-standpoint, aswellas from a scientific standpoint.

Now, I have found that I can separate chemi cally modified resins and chemically modified ros which is relatively simple, eificient and adaptable .to commercial operation. I accomplish this by treating a chemically modified rosin or a chemi cally modified resin ester with'a substance selected from the group of substances now known. to the art to be selective solvents for the visible and latent color bodies. of'iosin. I l The process in accordance with this invention 55 consists of treating a modified rosin or modified rosin ester with a solvent which is a selective solvent for the color bodies of rosin, separating j the selective solvent from theundissolved component of the modified rosin or rosin'ester and 60 recovering the component of the modified rosin 'which is a mixture of chemically different es realized that such separation would be of great" in esters into their components by a method dissolved therein, as, for example, byevaporating the-selective solvent. repeated as many times as necessary to produce the desired separation of the components;

In c arrying'out this method, the modified rosjins or rosin esters may or may not be first dissolved in a solvent therefor which is immiscible narily, it will be found'convenient to use such a solvent, particularly if the modified rosin or rcsin ester treated is a solid at the temperature of treatment; When it is desired to use a solvent forthe modified rosin or modified rosin ester, the procedurein accordance with this invention will consist of dissolving :the modified rosin or modifiedrosin ester in the solvent, contacting the'solution so'iormed with a selective rosin color ybody solvent immiscible therewith, separatingthe two solutions thus formed, and recovering a component of the modified rosin or modified rosin ester from each solution as, for example, by evapi-v.

crating the respective solvents, preferably under reduced pressure. This procedure may herepeated as many times as desired;

Afterseparating the'modified rosin or modified rosin ester into components by the above procedure; each component may be further purified by crystallization from-suitable solvents,- fracv tionation under reduced pressure, contacting with an absorbent,;such as, fullers earth, kieselguhr, activated carbon, etc.- I

-The modified' rosin or'modified rosin ester 1 which Tmajytreat in accordance with this invention' may beany rosin or rosin ester which has been treated to modify its chemical structure, so, that the resultant productis a mixture oi two or more chemicallydifierent substances. The hydrogenation of rosin or a rosin ester in the presence'of a suitable catalyst-according to methods 'knownto the artproduces such a modified rosin ormodifiedrosin ester. The esterification of a hydrogenated rosin, likewise, produces such an ester.

{The polymerization of rosin or a rosin ester, to increase its molecular weight and melting point by treatment with a polymerizing agent, for example, volatile metal halides; as, boron trifluorideyzinc. chloride, stannic chloride, 'al'umi-- This process ,1 can be with the selective solvent which is used. Ordi- 1 num chloride, ferric chloride; mineral acids, as,

sulfuricacid; phosphoric acid; fullers earth; hy-

ifate, etc.; metallics'ilicon; hydro fluoro-boric acid etc., according to methods known to the art, produces sucha modified rosin or modified rosin ester Such a modified rosin ester may also be produced by esterifying a polymerized rosin. -Again,. ..the treatment of'rosin or a rosin ester with a suitable catalyst, as, for example, a hydrogenation catalyst, as nickelf nickel chromite, platinum, palladium, etc., at an elevated tem-v drogenfluoride; acid salts, as sodium acid suli perature of, for example, from about 150 C. to about 200 C. and without reaction between the rosin or rosin ester and any added substance, to produce an intraand inter-molecular rearrangement within the hydrocarbon nucleus of the rosin or rosin ester with a reduction in' the apparent unsaturation as disclosed in the copending application of Edwin R. Littmann, Serial No. 84,877, filed June 12, 1936,- produces a'modified rosin or modified rosin ester which may be treated in accordance with this invention. Such modified rosins and modified rosin esters will hereinafter be termed Hyex rosins and .I-Iyex rosin esters, respectively. The esterification or a Hyex rosin also-produces such achemically modified rosin ester.

The modified rosins which I treat inaccordance with this inventio-n may be any grade of wood or gum rosin which has been treated to modify its chemical structure so that the product is a mixture of two or more chemically different materials. The esters of the modified rosins which I treat may be produced by the esterification of modified rosins or may be produced by the chemical modification of ordinary esters of rosins, and may be esters of'either'a monohydric or a polyhydric alcohol. Thus, esters of rosins with monohydric alcohols, such as, for example, methanol, ethanol, propanol, butanol, amyl alcohol, cetyl alcohol, lauryl alcohol, stearylalcohol, furfuryl alcohol, hydrofurfuryl alcohol, abietanol, hydroabietanol, phenol, benzyl alcohol, etc., or with polyhydric alcohols, such as, for example, ethylene glycol, diethylene glycol, triethylene glycol, glycerol, sorbitol, mannitol, erythritol, pentaerythritol, etc., may be treated by my new method.

The selective solvent which I use in accordance with this invention may be any of the various selective solventsfor the visible andlatent color bodies of rosins and rosin esters heretofore known. Thus, I may use furfural, furfuryl al-. cohol, a chlorohydrin, as, ethylene chlorohydrin, propylene chlorohydrin, etc., aniline, phenol, resorcinol, ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, trimethylene glycol, glycerol, butyl glycerol, ethyl formats, methyl acetate, methyl formate, methyl orthonitrobenzoate, methyl furoate, alkyl formats, monoacetin', diacetin, triacetin, ethyleneglycol monoacetate, methanol, hydroxyl alkyl amine, as triethanolamine, a. solution of oxalic acid in water or in methanol, ethanol or other lower aliphatic alcohol, ethylene glycol monoethyl ether, or other immiscible glycol ether, ethylene glycol monoacetate, or other immiscible glycol ester, methyl thiocyanate, ethyl thiocyanate, acetonitrile,

acetic acid, acetic anhydride, p-chloroaniline,

hyde, guaiacol, anisidin, nitroanisol, dichloroethyl ether, methoxy acetic acid, methoxybenzyl alcohol, liquid sulfur dioxide, nitromethane, etc., or mixtures of such refining agents which are chemically nonreactive, etc.

The solvent in which I may dissolve the modi fied rosin or modified rosin ester before contact-- ing it with a selective solvent may be any solvent for the modified rosin ormodified rosin ester which is immiscible and non-reactive with the selective solvent used. Thus, I may use a petroleum hydrocarbon solvent, such as, for example,

gasoline, petroleum ether, a normally gaseous petroleum hydrocarbon held in liquid phase by elevated pressure, low temperature, or both. The concentration of the modified rosin or modified rosin ester in such a solution may be within the range of about to about 80% by weight, and desirably within the range of about 15% to about 30% by weight.

The temperature at which the process in accordance with my invention may be carried out is dependent upon the selective solvent employed and will be within the range of about -40 C. to about +60 ,C. In any case, the temperature used will be such that the selective solvent is a liquid under the pressureused.

In the embodiment of my process in which a chemically modified rosin or a chemically modified rosin ester is dissolved in a solvent therefor before it is contacted with a selective solvent, the solution so formed may have a concentration within the range of about 5% to. about 40% by weight. Usually I prefer to use a solution having a concentration within the range of about to about 25% by weight.

The number of washes employed in my process may/be varied in accordance with the results desired, and it will be appreciated that the greater the number of washes given the sharper will be the separation of the components of the chemically modified rosin or chemically modified rosin ester treated. I

As illustrations of the practical adaptation of the method in accordance with this invention. I may cite the following:

EXAMPLE I .Wood rosin polymerized by treatment in solution in ethylene dichloride solution with aluminum chloride, washed with hydrochloric acid and then with water, and recovered by evaporation of the solvent was treated. One hundred grams of this polymerized rosin was dissolved in 300 grams of gasoline. This solution was washed with 75 cc. of furfural, with 25 parts by volume of furfural and then with two portions of 10 cc. of furfural. The furfural wash solutions were combined and evaporated to recover the component of the polymerized rosin dissolved therein. Likewise, the gasoline solution was evaporated to recover the component remaining therein.

The two components thus separated from the original polymerized rosin and a sample of the original polymerized rosin were tested by making them into core oils and observing the time required for the core oil to crystallize. The core oil made from the original polymerized rosin had crystallized in about 105 days, showing it to be non-crystalline. The component of the polymerized rosin recovered from the gasoline solution after treatment with furfural crystallized from core oil in five days showing it to be unpolymerized rosin. On the other hand, the componentlof the original polymerized rosin recoviii ered from the furfural had ote ystamied from core oil in one hundred and forty days, as compared With about one hundred and five days for the original polymerized rosin, showing it to be more highly polymerizedthan the original rosin. These core oil tests demonstrate that the process in accordance with this invention separated the ExAMPLnII A stock solution was prepared which contained 25% of rosin. The rosin present in this solution was composed of 50% 1- wood rosin and 50% I wood rosin hydrogenated to the extent of 50% of the theoretical for two double bonds. Three portions of this stock solution of 200 cc. each were counter-currently washed, with three portions of 200 cc. of iurfural at room temperature, .so that "the spent furfural from. the first stage successively passed on to stage 2 and finally The three furfural' washed gasoline stage 3. 7 solutions, and the three iurfural solutions, were evaporated to recover the rosin components dissolved therein. The various components thus secured were .ana'lyzed with the results given in analyses: 1 1

Table 2 Table 4 Refractive Hydroa v Speindex; genation m figg Acid Refraccific m e .1 g N o. tive index rotapom; tion Percent Percent Original hydrogenated rosin. 1.5255 60 y Fraction from gasoline solution Fraction from gaso-' O. Percent No. 1 1. 5218 78 44. 5 line sol. No. 1..-.. 75. 5 156. 5 1.537l +50. 21. 6 Fraction from gasoline solution Fraction from gaso- No. 2 l. 5230 74 66. 2 line $01. No. 2. 77. 160. 5 1. 5378 +54. 5 25. 6 Fraction from gasoline solution 1 Fraction from gaso- No. 3 1. 5243 68 81.1 line 501. No. 3. l. 82. 0 163. 0 1. 5382 +53. 4 32. 8 Fraction from combined furfural Fraction from furi fractions 1. 538 22 fural $01-- 90.0 161. 5 1. 5527 +60. 2 15, 2

I Table l which follows:

Table' 1 Refractive Hydroindex genation Grade Yield Percent Percent Original blended rosin. 1. 5361 32 H Rosin ironi'gasoline sol. I No.1 1. 5264 65" N+ 18. 7

Rosin from gasoline sol.

No. 2 1. 5312 '47. 5 N+ 67. 0 Rosin from gasoline sol. No. 3 1.5335 40.0 N 95.0 Fraction from combined 'furiuralwash solutions. 1.5422 0.0 37.0

inspection of the above. example shows that the original blended rosin having a 32% hydrogenation was separated into fractions which ranged from 0.0% hydrogenatio m 655% drogenation. o

' EXAMPLE III A hydrogenated 1 wood rosin saturated to the extent of I 60% was "used in this experiment.

Three portionsof 300 grams each were countercurrently washed with five portions of 100 cc. each of furfural. The resulting gasoline solutions and the combined furfural solutions were evaporated under reduced pressure. The products thus secured showed the following results on I by analysis.

that the saturation of the hydrogenated rosin recovered from the gasoline solution was increased to as high as 78%. As a comparison it will be noted that the rosin recovered from the furf ural was saturated to the extent only of 22%.

EXAMPLE IV A gasoline solution containing 13% Hyex wood rosin was'prepared. Three portions of this solu tion', each 300 parts by volume, were countercurrently washed with one portion of 50 parts by volume and six portions of 25 parts by volume, respectively,- of 85% aqueous phenol, whereby each rosinsolution received four washes. The gasoline solutions, and the combined phenol solutions were evaporated under reduced pressure to recover the rosin fractions dissolved therein. Analysis of. the' products so recovered showed them to have the following physical properties:

Table 3 Drop R enac Specific $235 tive index rotation l C'. Percent OnginalHyex rosin. 83 1.5426 Fraction from gaso ne $01. No. l 72 1. 5375 +52. 8 17. 5 Fraction from gasoline sol. N0. 2 78 1.5376 +53. 4 22. 5 Fraction from gasoline 1 I sol. No. 3 80. 5 1. 5400 +55. 4 31. 5 Fraction from aqueous phenoL. 86. 0 1. 539 +61. 4 21. 6

An examination of the above table shows that the'treatment separated the original Hye-x rosin into two components having quite different phys ical characteristicsirom one another. A comparison of the properties of the compo-nent'from gasoline solution 3 and those of the component from the aqueous phenol brings this out. the aqueous phenol component had a definitely higher melting point, a lowerrefractive index and ahigher specific rotation than the fraction from the gasoline solution. I 1

EXAMPLE V A gasoline solution containing Hyex rosin was prepared. 7 Three portions, 300 parts by volume of each,; of the solution were counter-currently washed with one portion of furfural of fifty parts by volume and four portions of fur- 'fural-of thirty parts by volume, so that each of the gasoline solutions received four countercurrent washes. The gasoline solutions andthe combined furfural wash solutions were evaporated under reduced pressure, and the properties or the rosin components recovered determined Table IV .which follows:

An inspection of the above table shows that the furfural wash removed unliydrogenated or slightly hydrogenated rosin from the hydrogenated rosin contained in the gasoline solution, so

; components show Thus, 7

Their characteristics are given in' In the above Table as in Table of Ex ample IV, the characteristics of the separated them to be difierenttypes of rosin,

nate at 0 C.,

EXAMPLE VI Three portions of a 20% solution of hydrogenated I grade wood rosin in gasoline of 200 grams each were counter-currently washed'with methyl thiocyanate at 25 C., so that each gasoline solution received five Washes with 20 cc, of methyl thiocyanate. The three refined gasoline solutions and the combined thiocyanate solutions were evaporated under reduced pressure to recover the rosin fractions dissolved in each. The analyses and yields of these fractions of the hydrogenated rosin, as wellas that of the original hydrogenated rosin, are given in Table 5 which follows:

An inspection of the data of Table 5 shows that the treatment with the methyl thiocyanate solution separated the hydrogenated rosin having a saturation of 62.5% of theoretical into fractions having saturations within the range of 67-72% of theoretical on one hand and 30% of theoretical on the other. Thus, the thiocyanate tended to selectively dissolve unhydroenated rosin. from the more highly hydrogenated rosin which remained in the gasoline solution.

EXAMPLE VII 'Three portions of a 20% solution of dihydroaloietyl alcohol in gasoline of 50 grams each were counter-currently washed with methyl. thiocyaso that each gasoline solution received five washes with 10 cc. portions of methyl thiocyanate. The three refined gasoline solutions and the combined thiocyanate solutions were evaporated under reduced pressure to recover the dissolved fractions. The analyses and yields of these fractions of the dihydroabietyl alcohol are given in Table 6.

Table 6 Weight gf Alcohol recovered D. H. A.

Percent Percent Grams Original dihydroabietyl alcohol... 4. 81 Dihydroabietyl alcohol from gas.

sol. No. l 4. 4 43 0.7 Dihydroabietyl alcohol from gas.

sol. No. 2 4. 65 60 2.0 Dihydroabietyl alcohol from gas.

s .No.3 4.7 11.8 Dihydroabietyl alcohol combined methyl thiocyanate sol 4.8 91.5 12.3

An inspection of the data of Table 6 shows that the original sample of dihydroabietyl alcohol was 81% alcohol, while the fraction recov ered from the combined methyl thiocyanate so lution was 91.5% dihydroabietyl alcohol. As compared with this the fraction recovered in the No. 1 gasoline solution was only 75% dihydroabietyl alcohol. Thus, the treatment in accordance with this invention definitely concentrated the alcoholic portion of the original dihydroabietyl alcohol in the methyl thiocyanate fraction,

EXAMPLE VIII Three portions of 100 grams each of a 20% I solution of dihydroaoietyl alcohol in gasoline were washed counter-currently with aniline at 0 C., so I that each gasoline solution received five washes with 10 cc. portions of aniline. The three refined gasoline soiutions and also the combined aniline.

solutions were evaporated under reduced pressure to recover the dissolved products. The analyses and yields of these products are given in Table 'l which follows:

Table '7 D. n. A. Hydroxyl Alcohol 533%? recovered Percent Percent Grams Original dihyrlroabietyl alcohol..... 4. 75 81 Dihydroabietyl alcohol from gas.

501. No. l 4. 4 75 9. 5 Dihydroabietyl alcohol from gas.

sol. No. 2 4. 65 78. 5 l6. 5 Dihydroabietyl alcohol from gas.

sol. No. 3.... 4. 7 80 19. 2 Dihydroabietyl alcohol from combined aniline solutions..... 4. 75 I I 82 11.3

An examination of the above data shows that aniline, like 'the methyl thiocyanate of the Example VII selectively dissolve the dihydroabietyl alcohol, yielding a fraction which was materially purer than the original sample.

EXAMPLE IX A glycerol ester of hydrogenated wood rosin (hydroabietic acid) was dissolved in. gasoline to a 20% concentration. Three portions of 200 cc.

each of this 20% solution were counter-currently washed at 25 C. so that each portion received six washeswith 20 cc. portions of phenol. The three refined gasoline solutions and the combined phenol solutions were evaporated under reduced pressure; The analyses and yields of the fractions thus recovered are given in Table 8.

Table 8 Refractive index at Yield Grams Original glycerol ester l. 5303 Ester from gas. sol. No. 1.... 1.5303 25 Ester from gas. sol. No. 2.. 1. 5303 35 Ester from gas. sol. No. 1.5314 37 Ester from combined phenol extract l. 5316 Since it is known that the less saturated products have higher refraction indices, a comparison of the refractive index of the original ester with that ol the fraction secured from the combined phenol extract shows that the latter contains less saturated material than the original, and is a definitely diiTerent material.

EXAMPLE X The methyl ester of hydrogenated wood rosin (dihydroabietic acid) was treated following exactly the same procedure as in Example IX with the exception that furfural, instead of 85 phenol, was used as a selective solvent. The analyses and yields of the recovered fractions of the ester are given in Table 9.

Table 9 Refractive Saturaindex tion Ylem Percent Grams Orig. methyl hydroabietate 1. 5177 40 Ester from gas. sol. No. 1 1v 5148 30 28 Ester from gas. sol. N o. 2 l 5163 43 31 Ester from gas. sol. No. 3. 1 5164 4.5 38 Ester from combined fur-fur ex 1 528 22 An examination of the data given in Table 9 shows that the hydrogenated abietyl ester was concentrated in the gasoline solution #1 while the unhydrogenated ester was concentrated in the furfural extract.

EXAMPLE XI The glycerol ester of Hyex wood rosin was dissolved in gasoline to produce a solution. Three portions of 200 grams each of this solution were counter-currently washed with furfural at room temperature C.) so that each.

portion received washes with six 20 cc. portions of furfural. The gasoline solutions and the combined furfural washes were then evaporated under reduced pressure. The analyses and yields of the recovered products are given in Table 10.

Table 10 Refractive Yield index Grains Orig. glyeeryl ester of Hyex rosin 1.5442 Ester from gas. sol. No. l 1.5432 25 Ester from gas. sol. No. 2. 1.5435 38 Ester from gas. sol. No. 3 1 5454 39 Ester from combined furfural ext 1 5552 21 A comparison of the refractive indices of the original ester, the fraction recovered from the #1 gasoline solution and. the fraction recovered from the furfural solution, shows that the original ester of Hyex rosin has been separated into two chemically different fractions bythefurfural wash.

EXAMPLE XII The glycerol ester of Hyex wood rosin was dissolved in gasoline to produce a 25% solution.

Three portions of 200 grams each of this sol'u tion were counter-currently washed with one 75 cc. portion and five 55 cc. portions of 85% aqueous phenol at room temperature (25 C.) The resulting gasoline solutions and the combined phenol solutions were evaporated under reduced pressure to recover the components dissolved in each. The results obtained are given in Table 11.

Table 11 Refractive Drop index melting Grade Yield 20 0 point 0'. Percent Orig. glycerol ester of Y Hyex rosin 1. 5454 87. 8 E+ Ester from gas. sol. No.1. 1. 5378 74. 0 -D 6.8 Ester from gas. sol. No. 2. 1. 5413 82. 5 D-l- 13.1 Ester from gas. sol. No. 3 1.5425 83.5 E+ 14. 7 Ester from combined phenol ext 1. 5478 88. 8 D 65. 4

A comparison of the refractive indices and the melting points Show that the original glycerol ester of Hyex rosin has been separated into chemically different fractions by the phenol wash.

Table 12 t s iii t we pec cm aindex tion Grade Yield 20 C.

Percent Origt. Hyex methyl 1.5301 +52.1 F es er.

EstIer {rem gas. sol. 1.5210 +53.8 WW+ 11.1 o.

Esltler grom gas. sol. '1. 5240 +556? WW 20.3

o. e r Estrer groin gas. sol. 1.5260 +553 WG 23.7

o. Ester from combined 1.5344 Not entirely -D 44.9

iurfural washes. soluble.

The differences in the refractive indices, spe- ,cific rotation and grade demonstrate the separation of the original methyl ester of Hyex rosin into components of different composition, properties and color. a

It will beunderstood that the above examples I and details, of operation are given by way of illustration only, and that the scope of my invention as herein broadly described and claimed is in no way limited thereby.

Where in the appended claims I have used the term I-Iyexf rosin or Hyex rosin ester it will be understood that I mean a rosin or a resin,

ester which has been chemically modified by an interand intra-molecular rearrangement within the hydrocarbon nucleus of the rosin or rosin ester as hereinbefore described.

This application forms a continuation-in-part of my application, Serial No. 160,725, filed August 24, 1937, entitled Method for the separa-, tion of chemically modified rosins and their esters into components.

What I claim and desire to protect by Letters Patent is:

1. The method of separating an ester of Hyex.

rosin into its components, which comprises dissolving the Hyex rosin ester in a solvent therefor, contacting the solution so formed with a selective rosin color-body solvent immiscible'with the'said solution, separating the selective sol vent therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions.

2. The method of separating an ester of Hyex rosin into its components, which comprises dissolving the Hyex rosin ester in a solvent therefor, contacting the solution so formed with a selective rosin color-body solvent immiscible withthe I said solution, separating the selective solvent therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent. I v

3. The method of separating an ester of Hyex rosin into its components, which comprises dissolving the Hyex rosin ester in a solvent therefor, contacting the solution so 'formed with furfural, separating the selective solvent therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

4. The method of separating an ester of Hyex rosin into its components, which comprises dissolving the Hyex rosin ester in a solvent therefor, contacting the solution so formed with phenol, separating the selective solvent therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

- 5. The method of separating an ester of Hyex rosin into its components, which comprises dissolving the Hyex rosin ester in a solvent therefor, contacting the solution so formed with an alkyl thiocyanate. separating the selective solvent therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

6. The method of separating an ester of Hyex rosin into its components, which comprises dis- 1 solving the I-Iyex rosin ester in a petroleum hydrocarbon solvent, contacting the solution so formed with a selective rosin color-body solvent immiscible With the said solution, separating the selective solvent therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

7. The method of separating an ester of Hyex rosin into its components, which comprises dissolving the Hyex rosin ester in a petroleum hydrocarbon solvent, contacting the solution so formed with furfural, separating the furfural therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

8. The method of separating an ester of Hyex rosin into its components, which comprises dissolving the Hyex rosin ester in a petroleum hydrocarbon solvent, contacting the solution so formed with phenol, separating the phenoltherefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

9. The method of separating an ester of Hyex rosin into its components, which comprises dissolving the Hyex rosin ester in a petroleum hydrocarbon solvent, contacting the solution so formed with an alkyl thiocyanate, separating the alkyl thiocyanate therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

10. The method of separating a glycerol ester of Hyex rosin into its components, which comprises dissolving the said ester in a petroleum hydrocarbin solvent contacting the solution so formed with furfural, separating the furfural therefrom and recovering a component of the Hyex rosin ester from each of the resulting solutions by evaporating the solvent.

JOSEPH N. BORGLIN. 

